|General features||Unit||iglide® A290||Test method|
|Max. moisture absorption at 73° F / 50% R. H.||% weight||1,7||DIN 53495|
|Max. moisture absorption||% weight||7,3|
|Coefficient of surface friction, dynamic, against steel||µ||0,13 - 0,40|
|p x v value, max. (dry)||psi x fpm||6,600|
|Modulus of elasticity||psi||1,276,000||DIN 53457|
|Tensile strength at 68° F||psi||36,260||DIN 53452|
|Permissible static surface pressure (68° F)||psi||10,150|
|Shore D hardness||88||DIN 53505|
Physical and thermal properties
|Upper long-term application temperature||°F||284|
|Upper short-term application temperature||°F||356|
|Lower application temperature||°F||-40|
|Thermal conductivity||[W/m x K]||0,24||ASTM C 177|
|Coefficient of thermal expansion (at 73°F)||[K-1 x 10-5 ]||7||DIN 53752|
|Specific volume resistance||Ωcm||> 1011||DIN IEC 93|
|Surface resistance||Ω||> 1011||DIN 53482|
For iglide® A290 plastic bushings running dry against a steel shaft, at 68° F.
iglide® A290 plastic bushings are an advanced development for the use in food and pharmaceutical industry. Compared to the bushings made of iglide® A200, the tribological properties could be significantly improved.
iglide® A290 plastic bushings have a recommended maximum surface pressure of 10,150 psi. At this load, the deformation at room temperature is only 2.5%. A plastic deformation is close to zero up to this load. However, it is also affected by the cycle time.
The short-term permitted maximum temperature is 356° F.
With increasing temperatures, the compressive strength of iglide® A290 plastic bushings decreases. The diagram 9.3 clarifies this connection.
The temperatures prevailing in the bushing system also have an influence on the bushing wear. The wear increases with rising temperatures, and the influence is especially marked from 248° F temperature onwards.
|iglide® A290||Application temperature|
|Lower||- 40 °F|
|Upper, long-term||+ 284 °F|
|Upper, short-term||+ 356 °F|
The coefficient of friction alters like the wear resistance with increasing load and surface speed.. With increasing speed and constant load, the coefficient of friction steadily rises. In contrast a reverse behavior is noticed at increasing load and constant speed (see Figures. 9.4 and 9.5) Friction and wear depend to a high degree on the reverse partner. Very smooth shafts increase the coefficient of both friction and wear. iglide® A290 proves to be relatively insensitive to shaft surfaces and retains a 0.4 friction coefficient µ with average surface finishes of Ra = 0.4 to 1.6 µm.
|Coefficients of friction µ||0,13 - 0,40||0,09||0,04||0,04|
The graph displays a summary of the results of tests with different shaft materials conducted with plastic bushings made of iglide® A290.
Compared to iglide® A200, the improved tribological properties of iglide® A290 are also reflected in the coefficients of wear. At low loads, the differences in the wear resistance of the combinations of iglide® A290 with different shaft materials are very distinct. Figure 9.8 shows that the advantage of hard-chromed shafts increases with rising load. This counter partner is also well-suited for pivoting applications and are frequently found in packaging machines. Other hardened surfaces are also recommended for oscillating movements, for example 1050 hardened and ground steel.
|Shaft h9 |
|iglide® A290 |
|Up to 0.5||0 - 0,025||+0,020 + 0,080|
|> 3 to 6||0 - 0,030||+0,030 + 0,105|
|> 6 to 10||0 - 0,036||+0,040 + 0,130|
|> 10 to 18||0 - 0,043||+0,050 + 0,160|
|> 18 to 30||0 - 0,052||+0,065 + 0,195|
|> 30 to 50||0 - 0,062||+0,080 + 0,240|
|Alcohol||+ to 0|
|Greases, oils, without additives||+|
|Weak acids||0 to -|
|Strong alkaline||+ to 0|
|Specific forward resistance||> 1011 Ωcm|
|Surface resistance||> 1011 Ω|
iglide® A290 plastic bushings have a good resistance against chemicals. They are resistant to most lubricants. The iglide® A290 is not affected by most weak organic and inorganic acids.
The moisture absorption of iglide® A290 plastic bushings amounts to about 1,7% in standard climatic conditions. The saturation point in water is at 7.3%, a disadvantage which must be accounted for by all means in applications in humid and wet areas.
Please contact us if there is any query about clearance design in humid applications.
iglide® A290 plastic bushings are radiation resistant up to a radioactive intensity of 3 x 10² Gy.
iglide® A290 plastic bushings are resistant to UV radiation, but the tribological properties deteriorate.
The iglide® A290 plastic bushings can be used in vacuum only restrictedly due to the high humidity absorption.
iglide® A290 plastic bushings are electrically insulating.